A recurring problem in the metal working field is obtaining adequate rigidity of working tools so that they do not upon performance of cutting operations yield or otherwise deflect to an extent which produces work of unacceptable tolerances. This is a particular problem in boring procedures, particularly when forming large diameter holes of substantial depth. Accordingly, as the diameter and depth of the hole to be bored increases, so generally does the diameter and length of the bar which supports the cutting tool in order that the tool be sufficiently rigid so that the resultant hole will be within acceptable tolerances. Thus the selection of a sufficiently large, i.e. rigid, boring bar for a particular purpose not only requires experience of the tool operator, but furthermore necessitates maintenance of a large inventory of boring bars, and even the requirement for different sized machine tools in order to accommodate such boring bars. This is not economical or feasible with many small or specialty oriented machine shops, and accordingly, it would be desirable to have available a tool system which provides for the satisfactory boring of holes of various depths and diameters without the necessity of maintaining a large inventory of tool holding bars.
Attempts to provide such capabilities have been made in the past and one such system is described in U.S. Pat. No. 2,399,271 issued Apr. 30, 1946. Therein a boring bar system comprising two parallel tool supporting rods is disclosed wherein each of the rods or bars is provided with a passage or slot at one end to cooperatively receive and support a tool. The support of the tool at spaced locations additionally serves to stabilize the tool during cutting operations. While functional, this system restricts the independent positioning of the supporting rods with respect to each other as well as relying upon the tool itself to provide the stabilizing effect between the two supporting rods.
Accordingly, it is an object of the present invention to provide a tool holding system in which a tool supporting bar is mounted with respect to a second independently movable stabilizer bar in such a manner that the initial tool holding bar is capable of either independent operation with or without the stabilizing bar.
Another object of the invention is the provision of a tool bar and stabilizer bar, whereby such bars are interconnected by means of a rigid member in such a manner as to stabilize movements of the tool during the cutting action thereof on the work piece.
A further object of the present invention is the provision of a tool stabilizing system of the type aforementioned in which the rigid member which serves to interconnect the tool supporting bar with the stabilizing bar is adapted for varying longitudinal disposition with respect to such bars.
A still further object of the present invention is to provide a novel holding device for a work tool stabilizing system including a first tool supporting bar interconnected to a generally parallely disposed stabilizer bar by means of a rigid interconnecting member, wherein the ends of said bars remote from the tool are positioned within spaced openings provided therein so as to affect such spaced bar disposition in varying attitudes dependent upon the configuration of such holding member or block.
A still further object of the invention is to provide means for laterally adjusting the position of a tool in position with respect to a tool holding bar by the use of a rigid member which interconnects such tool holding bar and a parallel disposed stabilizer bar at eccentric end portions of such bars in such a manner that rotation of such bars is translated into lateral adjustment movement of the tool.
Other objects, features and advantages of the invention shall become apparent as the description thereof proceeds when considered in connection with the accompanying illustrative drawings.